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Discussion Starter #1 (Edited)
Hello fellow members looking for advice from someone smarter than me on these yota's.Brief history of what's going on,I've picked up a pesky misfire on 3 and 6.I have looked at Compression on all cylinders#169 to 179 on all cylinders.I have taken fuel rails off and cleaned injectors and ohm all them also all checked out.Checked ohm's on cam sensor 1100 ohms on cold engine.Changed fuel filter since I cleaned injectors,also did smoke test on engine to see if had any leaks from vacuum or intake gaskets,also checked good.Changed plugs,also have spare coils that I have tried all oem.Just for bud light sake I swapped coils around still misfire on same cylinders.Starting to think she jumped time,my Question is there any thing else I could check,and is there a easier way to check timing on this 4.7?Also my fuel trim on bank 2 is high to me it's running plus 20 bank 1 is running 3.4 on long term.Seems high to me on bank 2.Thanks in advance looking forward to every ones advice.Forgot to add it's 01 4.7 with 214000 miles last belt was done at 105000
 

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You can pull the upper timing covers and look at the cam pulleys. There is a line on the head that matches a mark on the pulley at top dead center. But if you had jumped time, the whole bank would be missing.

You're fuel trims for bank 2 are way too high, I imagine you have set a lean code. Check the fuel trims holding the engine at around 4000 RPM in park. Do the fuel trim go down? If so, you should look for a vacuum leak on that bank. If not, I would also look at the downstream O2 sensor, and see if it is biased one way, making the ECU think the car is running lean, and it dumping more fuel on that bank.
 

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Type of spark plug?
Has the missfire remained on 3 and 6 through everything?
Have you cleared the codes and it for sure comes back on those two?
Is it actually running rough or just the codes? (missfire at cruise kinda thing is what I was thinking)
Being 3 and 6 are on different banks it doesnt sound like the lean condition is the cause maybe more of of outcome, like the un-burnt oxygen is skewing readings?
When you removed the injectors for cleaning did you put them back in the same place? Or did you move them around and missfire remained?
Can you place a long screw driver on each injector and listen for a strong click to see if any of them sound different? (could have an inj signal issue)
Generally speaking your compression will be low if timing is off, id be happier with 175-190 psi.
Along the lines of inj signal you could have a bad signal to the coils as well. Do you have na inline spark tester to remove the coil and see what is going on?

Good luck and let us know how is goes.
 
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